Loyalty is a key attribute of an effective leader. When we normally think of a leader's loyalty we think of the leader's allegiance to the organization and its mission. But, loyalty is more complex for the effective leader.
An effective leader is loyal to his or her staff. The leader demonstrates loyalty by empowering their staff, taking the time to get to know them individually, and trusting them. A leader also represents the interests of the team when working with other leaders or senior management.
This doesn't mean that an effective leader is always nice or always believes the staff member. Sometimes leaders must take developmental or disciplinary steps. In some ways, even these acts are a demonstration of loyalty. When discipline is administered effectively the staff member's performance will typically improve and the leader should acknowledge this and give the person a "fresh start." Of course, discipline does not always turn out good and the person continues their poor behavior. In that case, the leader must be prepared to take further steps.
Loyalty also includes knowing when staff members need coaching or conversations regarding their performance. Leaders also should "walk the floor" to know what each staff member's job is, what problems they face, and how the leader can help them do a better job.
An hour a week simply talking with staff members goes a long way toward developing an effective staff and also toward developing staff loyalty to the leader and the organization.